This invention relates to an inspection apparatus and method, and in particular to an inspection apparatus and method for non-destructively inspecting the sub-surface structure of a test object.
The term “non-destructive testing” encompasses a number of techniques that can be used to evaluate the properties of a material, component or system without causing damage. These techniques are particularly used in the automotive and aerospace industries to assess sub-surface damage or material flaws. It is vital that this work is carried out to a high standard in the aerospace industry particularly, since damage that is not visible on the external surface of the aircraft may nonetheless compromise its structural integrity in the air. For this reason aerospace authorities apply stringent conditions to those who are authorised to inspect aircraft and pronounce them fit to fly. An aircraft often needs to be inspected at a location where there are not any individuals that are sufficiently qualified to undertake that inspection, however.